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    <title>Document</title>
    <script>
        // 输出0,5,10,15，....，50这些数，（扩展：统计这些数有多少个）
        var num = 0
        for(var i = 0; i <= 50; i += 5) {
            console.log(i);
            num++
        }
        console.log(`个数：${num}`);

    </script>
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